Societies and Academies

Abstract

PARIS. Academy of Sciences, September 13.—M. Léon Guignard in the chair.—F. E. Fournier: The apparent displacement of some stars in the total eclipse of the sun of May 29, 1919.—A. Blondel: The calculation of electric cables by the use of vectorial functions with real notation. The method described has the same advantages as when imaginary quantities are employed, but only real quantities are utilised in the demonstration. It is based on the introduction of vectorial series.—V. Smirnoff: Some points of the theory of linear differential equations of the second order and automorphic functions.—E. Jouguet: The velocity of waves in elastic solids.—C. Gamichel: The transmission of energy by the vibrations of water in pipes. Remarks on some recent publications of M. Cons tan tinescu, and a statement of the work done by the author on the same subject.—E. Canals: The estimation of calcium and magnesium in different saline media. A study of the conditions under which, in acetic acid solutions, it is possible to separate completely calcium and magnesium from salts of iron and aluminium.—G. Zeil: The rôle of building corals in lithospheric re-adjustments.—C. Störmer: Some rays of aurora observed on March 22, 1920, which reached a height of 500 km. The aurora borealis of March 22 was photographed from seven stations under favourable conditions. The stations were connected by telephone, and simultaneous photographs were taken from two or three stations at a time. About 620 photographs were obtained, and they show that the summits of some of the rays reached an altitude of 500 km. above the earth.—A. Chevalier: The origin of the cider apple-trees cultivated in Normandy and Brittany.—F. Viès: The spectral properties of the tetanus toxin. Spectrophotometric studies of the ultraviolet absorption spectra of the effects of heating and of the addition of antitoxin to solutions of the tetanus toxin.—A. Marie and L. MacAuliffe: The influence of life in Paris on the race. A study of 1509 Parisians of the poorer classes, 850 of whom were born of provincial parents, 294 of Parisian parents, and the remainder of one Parisian and one provincial parent. The Paris climate and town life lead to modifications which are thus summarised: The hair and eyes less pigmented than in the rest of France, more marked cranial development in proportion to height, and shortening of the limbs.—J. L. Dantan: Budding in Antipathella subpinnata and Parantipathes larix.